1. Field of the Invention
The present invention relates to dentistry equipment, and, in particular, to dental reamers.
2. Description of the Related Art
Dental reamers having one, two, or three spiral grooves have already been described. For example, French patent application 82 20903 describes a dental reamer that tapers down to its tip, of the type having three spiral grooves with a progressive pitch such that the free spaces between the cutting edges increase as one moves from the tip of the reamer towards its handle.
Although French patent application 82 20903 provides an improvement over dental reamers having only one or two spiral grooves, the improvement is limited. In practice, the dental reamer proposed in French patent application 82 20903 has been found to result in undesirable spiral displacement in the canal to be reamed during the continuous rotation of root canal treatment. As used in this specification, spiral displacement refers to the tendency of reamers of the prior art to advance within the canal as a result of the rotation of the reamer itself, rather than solely as a result of pressure applied by the dentist. If spiral displacement occurs, the dentist will not have complete control over the reaming process which can lead to serious problems for the patient.
The present invention addresses this limitation in the prior art. Further aspects and advantages of this invention will become apparent from the detailed description which follows.